Bernoulli's principle

Bernoulli's principle, theorem of aerodynamics stating that the pressure of a moving gas will be lowest where its speed is highest, or that a moving fluid conserves energy. The theorem, named after Swiss mathematician Daniel Bernoulli (1700–82), explains how airplane wings create lift. Because the air flow is faster across the wing's curved top surface than across its flat underside, air pressure is greater under the wing than over, creating lift.

See also: Aerodynamics; Hydraulics.